Jihepu DFY-30/20 Cryogenic Circulating Thermostat

Overview

The Jihepu DFY-30/20 Cryogenic Circulating Thermostat is an engineered laboratory temperature control system designed for precise, stable thermal management of external reaction vessels—including rotary evaporators, jacketed reactors, and synthesis flasks—within a wide operational range from –20 °C to +99 °C. Its core architecture integrates a hermetically sealed R22 refrigeration circuit with a high-capacity electric heating module and a robust, fully sealed circulation pump, enabling simultaneous cooling and heating while maintaining tight thermal stability (±0.5 °C) across its full setpoint range. Unlike basic chillers or water baths, the DFY-30/20 functions as a closed-loop heat transfer station: it circulates thermally conditioned fluid through external equipment via dedicated inlet/outlet ports (4# NPT), delivering consistent thermal load balancing essential for exothermic or endothermic chemical processes, crystallization studies, low-temperature catalysis, and controlled solvent removal. The system’s temperature regulation is governed by a digital PID controller interfaced with a calibrated PT100 platinum resistance thermometer, ensuring traceable, repeatable performance compliant with general laboratory quality requirements.

Key Features

• 30-liter stainless-steel bath reservoir with optimized geometry (Ø350 × 350 mm) supporting large-volume reaction setups and compatible with standard 30-L jacketed reactors or rotary evaporators.
• Dual-mode thermal actuation: independent high-power heating (3000 W) and variable-capacity refrigeration (1801–3729 W), allowing rapid ramping and fine-grained stabilization at any point in the operating range.
• Hermetically sealed, low-maintenance circulation pump (100 W, 20 L/min flow, 4–6 m head, 2 MPa max. pressure) with zero leakage design—critical for long-duration unattended operation and compatibility with organic solvents and corrosive media.
• Comprehensive safety architecture including compressor high-pressure cut-off, pump thermal overload protection, ground-fault interruption, and real-time self-diagnostic monitoring of temperature regulation integrity.
• Nickel-plated copper condenser coil and powder-coated steel enclosure ensure long-term corrosion resistance in humid or chemically active lab environments.
• Digital interface with 1 °C display resolution, programmable setpoints across –150 °C to +100 °C (sensor-limited range), and intuitive electronic temperature setting and readout.

Sample Compatibility & Compliance

The DFY-30/20 is intended for use with externally jacketed glassware, metal reactors, and condensation systems requiring external thermal coupling. Its 4# NPT inlet/outlet ports (low-in/high-out configuration) accommodate standard silicone or PTFE-lined insulated tubing (supplied). While not certified to IEC 61000 or ATEX as standard, optional explosion-proof configurations are available per customer specification—enabling safe operation in Class I, Division 1 hazardous locations when properly installed and grounded. The unit meets general electrical safety requirements per GB 4793.1 (equivalent to IEC 61010-1) for laboratory equipment. Its temperature control performance supports GLP-aligned documentation practices when integrated with external data loggers; however, native 21 CFR Part 11 compliance requires third-party validation of connected software systems.

Software & Data Management

The DFY-30/20 operates via embedded firmware with no proprietary software dependency. All temperature setpoints, real-time bath readings, and status alerts (e.g., “high pressure”, “pump overtemp”) are displayed locally on the front-panel LCD. For integration into automated workflows, analog 0–10 V or 4–20 mA output signals (optional add-on) can be configured to feed external PLCs or SCADA systems. Data logging requires connection to a standalone recorder or PC-based DAQ system. The unit does not store historical temperature logs internally nor provide USB/Ethernet connectivity—consistent with its design as a deterministic, maintenance-light thermal utility rather than a data-centric instrument.

Applications

• Temperature-controlled rotary evaporation of heat-sensitive compounds below ambient, minimizing decomposition during solvent removal.
• Exothermic reaction management in 30-L jacketed reactors, where precise sub-zero cooling offsets enthalpy-driven thermal runaway.
• Low-temperature crystallization trials requiring sustained –15 °C to –5 °C plateaus with minimal drift.
• Calibration of low-temperature sensors and reference probes across the –20 °C to +30 °C range using traceable PT100 feedback.
• Thermal conditioning of analytical accessories—e.g., chilled GC injectors, cooled detector housings, or cryo-trapped sampling lines.
• Material testing under controlled thermal stress, including polymer gelation kinetics and phase-change behavior in formulated systems.

FAQ

What is the lowest temperature achievable under typical lab conditions?
Under ventilated, no-load conditions at ambient 20 °C and 65 % RH, the unit reaches –22 °C. With a 30-L reactor containing 20 L of water-glycol mixture, the practical lower limit is –20 °C at steady state.
Can the DFY-30/20 be used with flammable solvents?
Standard configuration is not rated for flammable vapor environments. An explosion-proof variant—featuring intrinsically safe controls, purged enclosures, and non-sparking components—is available upon request and subject to site-specific hazard assessment.
Is remote monitoring or control possible?
No built-in network interface exists. Remote operation requires external hardware integration via analog signal outputs or third-party relay modules connected to the unit’s dry-contact alarm terminals.
What maintenance intervals are recommended?
Compressor oil and refrigerant levels require verification every 24 months under continuous operation; condenser coil cleaning is advised quarterly in dusty environments. The circulating pump requires no scheduled maintenance but should be inspected annually for seal integrity and flow consistency.
Does the unit include magnetic stirring?
Yes—a 40 W integrated magnetic stirrer is provided, compatible with standard PTFE-coated stir bars up to 80 mm length, suitable for homogenizing bath fluid or assisting heat transfer in viscous media.